In many communications networks which are presently used for telephony or telephony like services a calling party is normally provided with the option of not having to reveal his identity to the called party during call set-up and during the call. This feature, which enables a subscriber who has registered as an anonymous subscriber at his operator as an anonymous subscriber to maintain anonymous during the call, is available both in stationary, as well as wireless communication networks. When registered as an anonymous subscriber, such a calling party will typically be presented to a called party as “Anonymous”, “Unknown” or with any other corresponding expression, rather than with his telephone number or any type of network identity. While the option of barring exposure of the network identity to the called party is often beneficial to the anonymous calling party, the called party may in many situations consider the information presented to him as much to sparse, since there is no way for the called party to make any kind of distinction between different anonymous calling parties.
Today, certain support for handling anonymous calls to at least some extent, exist in some communication standards. One such service is Anonymous Call Rejection (ACR). Services like ACR can, however can only be used for handling any anonymous call and thus all anonymous calls are handled the same way, without making any distinction between different anonymous calling parties.
A simplified scenario for setting up a call between an anonymous calling party 100 and a called party 103 can be described according to the scenario below with reference to the simplified signaling diagram of FIG. 1. It is to be understood that FIG. 1 is a simplified illustration where nodes and entities which are normally necessary for providing communication functionality but which are not necessary for the understanding of the call set-up procedure have been omitted for simplicity reasons. This also applies for the other scenarios described below with reference to FIGS. 2-4.
From hereinafter a calling party is to be referred to as a user device which is registered to a user, wherein the user device is configured to provide access to at least some communications network and to enable for the calling party to set up outgoing telephone calls as anonymous calls. In a corresponding way a called party is to be referred to as a user device registered to another user, wherein the second user device is configured to handle incoming anonymous calls.
An anonymous calling party 100, accessing a communication network via an access node, here represented by the first network node 101, is initiating a call to a called party 103 via another network node, here represented by second network node 102 as indicated with a first step 1:1. At the second network node 102 a calling party identification procedure is initiated, as indicated with another step 1:2, for the purpose of identifying the calling party to the called party. In the present scenario the calling party 100 is identified as being an anonymous calling party, which does not want to reveal its network identity to any called party upon call set-up, and thus instead of forwarding the identity of the calling party 100 to the called party 103, the text “Anonymous” or “Unknown” is typically presented at the display of a user device of the calling party 100, as indicated with a next step 1:3. In a next step 1:4, the called party 103 has accepted the incoming call and the call is set up and may continue for an arbitrary time interval, until the call is terminated by any of the parties, as indicated with a subsequent step 1:5.
If the same calling party 100 at a later occasion makes a new call to the called party 103, as indicated with a subsequent step 1:6, it will not be possible for the called party to be aware that this is the same calling party as for the previous call, when steps 1:7 and 1:8 are executed. The called party 103 will only be informed from the network that yet another call from some anonymous calling party is being set up.
With the exception for malicious calls that can be handled via services like Malicious Call handling service (MCID), which is an integrated Services Digital Network (ISDN) service that is sometimes found in conventional communication networks or the like, there is presently no way of making a called party aware of whether he has previously received any call from an anonymous calling party.
Consequently, there is no known way of how to distinct different anonymous calling party from each other and thus how to allow the called party to decide how to treat such an anonymous incoming call. Especially in situations where calls are frequently received from anonymous calling parties it can be very annoying for the called party to be disturbed by receiving anonymous calls, not knowing whether such calls are unwanted calls, while at the same time not wanting to risk to miss any wanted call.
Also in situations where calls from anonymous calling parties are only received occasionally it may be annoying not to be able to identify the calling party. A situation may even arise where the calling party does not even want to appear as anonymous to a particular called party, but only to other called parties in general. Also in these situations there is no known method for allowing the called party to make any kind of distinction between different anonymous users.